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One pickup is small, with an impedance of 80 ohms, and the other pickup is slightly larger, with an impedance of around 900 ohms.
For my purposes, I labeled these pickups as "wide" or "narrow." One pickup is around 10 mm wide, and the other is about 12 mm wide.
The cards are labeled as version "A." The published Roland documentation supports version "B: and "C." These rare "A" cards are unusual in several ways: the component layout is very different and the outputs trimmers seem to be arbitrarily placed on the board.
You can also see jumper wires soldered across the board.
If there is one guitar that has become the "gold standard" of guitar synthesizers, it has to be the Roland G-303 guitar.
No doubt much of the popularity of the G-303 comes from Pat Metheny, who has played this guitar year after year on stages across the world, always amazing audiences with the moving and emotional quality of the G-303 and GR-300 rig.
It is difficult to see in the photos, but on the standard cards, version "B" and "C", three op-amps, IC1, IC2 and IC3 are used to amplify the signals to line-level for the GR-300.According to the schematic, these resistors should be 10K, but in this rare G-707 circuit board, the resistors were only 1K.This 10:1 ratio difference is in keeping with all the other changes.Es muy importante la correcta datación de tu instrumento, así como el lugar de fabricación.La mayoría de las veces un determinado año, país, o hasta la planta de montaje determinan su valor y orientan al luthier sobre materiales, técnicas y acabados de un instrumento en concreto. Aquí puedes encontrar algunos enlaces para conocer el lugar y fecha de nacimiento de tu guitarra o bajo.
The other vintage controllers, the G-202 and G-505, are well-built, fine guitars.